JP2002210745A - Method for manufacturing mold and replica master as well as mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that a plurality of pieces of a mold of a highly precise dimensional shape having a molding cavity of a complicated form or a thin-walled part of a mm unit, cannot be easily manufactured. SOLUTION: This method for manufacturing the mold comprises the steps to manufacture the mold having the molding cavity of the same shape as cavities 12 and 16 of a matrix 13 with the use of a replica master of a corresponding shape to the cavities 12 and 16 of the matrix 13. That is, the step for filling the cavities 12 and 16 with a reactive curable resin 18 in such a way that the resin 18 swells from the upper edge 19 of the matrix 13, the step for curing the reactive curable resin 18, the step for machining the upper edge 19 of the cured resin 18 smoothly, the step for joining a release plate 21 integrally to the upper edge 20 of the machined resin 18 through an adhesive and the step for drawing a pattern of the resin 18 as the replica master 23 from cavities 12 and 16 by releasing the release plate 21 from the matrix 13, are incorporated in the method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a mold having a molding cavity having the same shape as the cavity of the mother mold by using a replica master having a shape corresponding to the cavity of the mother mold, and a replica manufactured by the method. Regarding master and mold.

[0002]

2. Description of the Related Art In general, when a large number of optical components such as small-diameter aspherical lenses, microlenses, lens arrays, and diffraction gratings, and components requiring precise dimensions and shapes are manufactured in large quantities, a manufacturing method by molding is used. Adopted. A mold used for such a forming process tends to be extremely expensive because it is subjected to high-precision machining. For this reason, when manufacturing a plurality of identical dies, a method is used in which one mother die is manufactured by machining, and the same mold is duplicated by electroforming using this mother die. However, the electroforming process requires a very long manufacturing time due to a low plating rate, and the delivery time of a mold by such a manufacturing method is significantly delayed. By manufacturing a plurality of dies by machining and applying electroforming to a plurality of dies at the same time, such problems related to delivery can be solved to some extent, but the dies themselves become extremely expensive. There is no.

[0003] As a method for manufacturing a mold having the same shape at a low cost in a short period of time, a method using an ultraviolet curable resin has been proposed. Since this UV-curable resin undergoes shrinkage during curing, some contrivance is required to obtain high dimensional accuracy. For example, Japanese Patent Application Laid-Open No. 1-171932 proposes a method in which a transfer operation is repeated a plurality of times on a cavity of a mother die to improve the transferability of an ultraviolet curable resin serving as a replica master to the cavity. Have been.

[0004]

Problems to be Solved by the Invention
According to the method disclosed in Japanese Patent Publication No. 2 (1995) -207, since the transfer operation is repeated a plurality of times to improve the transferability of the ultraviolet-curable resin serving as the replica master, the dimensional accuracy of the replica master gradually increases by repeating the transfer operation. Although improved, the processing time increases with the repetition of the transfer operation, resulting in a problem that the manufacturing cost of the replica master increases. In addition, in this method, it becomes increasingly difficult to repeatedly supply the resin to the details of the complicated cavity due to repetition of the transfer operation for a master having a cavity having a complicated shape, and a high-precision replica master is required. On the contrary, there is a problem that manufacturing is difficult.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for easily manufacturing a mold having high precision dimensions and a shape having a molding cavity having a complicated shape and a thin portion in a unit of mm, and a replica master and a metal manufactured by the method. Is to provide a type.

[0006]

According to a first aspect of the present invention, there is provided:
A method of manufacturing a mold having a molding cavity having the same shape as the cavity of the master using a replica master having a shape corresponding to the cavity of the mother, wherein a reactive cured resin is formed from an upper end surface of the master. Filling the cavity so as to swell, curing the reactive curable resin, machining the upper end surface of the cured reactive curable resin smoothly, and machining the reactive curable resin. Integrally bonding a release plate to the upper end surface of the mold via an adhesive, and removing the release cured plate from the matrix, thereby removing the reactive cured resin from the cavity as a replica master. It is characterized by having.

According to the present invention, during the curing of the reactive curable resin, the reactive curable resin contracts freely in the cavity of the matrix, and due to this contraction, the reactive curable resin adheres to the cavity without being separated from the surface of the cavity. As a result, the transferability of the reactive cured resin serving as the replica master is secured.

According to a second aspect of the present invention, there is provided a replica master manufactured by the mold manufacturing method according to the first aspect of the present invention.

According to a third aspect of the present invention, there is provided a step of electroforming the die-cut reactive hardening resin, and a step of machining the electroformed die material as a die.
Removing the reactive cured resin from the machined mold. The mold according to the first aspect of the invention, further comprising:

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the method of manufacturing a mold according to the first aspect of the present invention, the step of filling the cavity with the reactive hardening resin is performed so that the reactive hardening resin does not overflow from the cavity. A step of filling the resin, a step of curing the filled reactive curing resin, and a step of filling the reactive curing resin further from above the cured reactive curing resin so as to rise from the upper end of the cavity of the matrix. Can have.

Before the step of curing the reactive cured resin, it is possible to further comprise a step of defoaming the reactive cured resin filled in the cavity. In this case, the step of defoaming the reactive cured resin is preferably performed in a vacuum atmosphere.

Performing an electroforming process on the die-cut reactive hardening resin, machining the electroformed die material as a mold, and removing the reactive hardening resin from the machined die. And removing. In this case, the step of removing the reactive cured resin from the cavity may include the step of abutting a knock pin against a release plate and separating the reactive pin from the matrix.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a mold manufacturing method according to the present invention will be described in detail with reference to FIGS. 1 to 9. However, the present invention is not limited to such an embodiment, and claims in this specification are not limited. The present invention can be applied to other technologies that should be included in the concept of the present invention described in the range described above.

The inner core 11 constituting a part of the matrix in the present embodiment has a cross-sectional shape as shown in FIG. Is formed in the surface by electric discharge machining or the like. The shapes and dimensions of the inner core 11 and the cavities 12 can be changed to arbitrary shapes other than the embodiment according to the shape and dimensions of the target molded product.

Next, FIG. 2 incorporating this inner core 11
The matrix unit 13 shown in FIG. The matrix unit 13 in this embodiment includes the inner core 11 described above,
An outer core 14 fitted around the inner core 11 so as to surround the inner core 11 and constituting a matrix in the present invention with the inner core 11;
And a connecting plate 15 for integrally connecting the outer core 1 to the outer core 1.
4, a cavity 16 is formed following the cavity 12 of the inner core 11, and the outer core 14 and the connecting plate 15 have
A plurality of knock pin through holes 17 for slidably inserting a knock pin described later are formed. In the present embodiment, the matrix is composed of the inner core 11 and the outer core 14, but it is of course possible to construct this with a single member.

The cavities 12 and 16 of the matrix unit 13 are immersed in isopropyl alcohol and subjected to ultrasonic cleaning, and then, the cavities 12 and 16 are improved in releasing property of an ultraviolet curable resin described later. The organosilane diluted with isopropyl alcohol was immersed in the cavities 12 and 16 of the matrix unit 13.

Next, as shown in FIG. 3, a urethane acrylate-based ultraviolet curable resin 18 as a reactive curable resin according to the present invention is filled so as not to overflow from the cavities 12 and 16, and then subjected to vacuum defoaming treatment. Then, it is confirmed using a microscope or the like that the ultraviolet curable resin 18 is in close contact with the cavity 12. Then, the vacuum defoaming process is repeated until it can be confirmed that the ultraviolet curable resin 18 is completely adhered to the cavities 12 and 16.

Thereafter, ultraviolet rays having an illuminance of 0.4 mW / cm ² are irradiated on the ultraviolet-curable resin 18 filled in the cavities 12 and 16 of the matrix unit 13 for 8 minutes, and after being pre-cured, Further, ultraviolet rays having an illuminance of 18 mW / cm ² were irradiated for 2 minutes to completely cure the ultraviolet curable resin 18.

Similarly, the cured ultraviolet curable resin 1
Further, a new ultraviolet curable resin 18 is supplied on the upper surface 8 so as to rise from the upper end surface 19 of the matrix unit 13 as shown in FIG. 4, and the illuminance of the new ultraviolet curable resin 18 is 18 mW / Irradiation with ultraviolet light of cm ² was performed for 5 minutes to completely cure the new ultraviolet curable resin 18.

Thereafter, the cured ultraviolet curable resin 18
Was machined into a flat smooth surface 20 as shown in FIG.

In this embodiment, the UV-curable resin 18 is used as the reactive curable resin. In addition, a thermosetting or room temperature-curable epoxy resin, a silicone resin,
It is also possible to use a polyester resin, a urethane resin, or a resin that is cured by an energy source other than ultraviolet rays, for example, infrared rays, visible rays, electron beams, X-rays, and the like.

Next, as shown in FIG.
Then, the release plate 21 is integrally joined using an adhesive (not shown) or the like. As the release plate 21, a metal plate, a plastic plate, or the like can be adopted. After waiting for the adhesive to sufficiently exert its strength, the dowel pins 22 are inserted into the dowel pin through holes 17, respectively, and the tips of the dowel pins 22 are brought into contact with the release plate 21, and as shown in FIG. Are largely projected from the upper end surface of the matrix unit 13 so that the cavities 12 and
From 16, the ultraviolet curable resin 18 is released together with the release plate 21 to obtain a replica master 23. The replica master 23 of the present embodiment, which includes the ultraviolet curing resin 18 and the release plate 21, is transferred with a narrow concave portion of the matrix unit 13, a cavity 12 having a complicated shape, and a molding surface 24 corresponding to high precision. Have been.

Next, an electroforming process as shown in FIG. 8 is performed by using the replica master 23 to form an electroformed layer 24 covering the molding surface 24. Then, after performing machining so that the electroformed layer 24 has the same shape as the inner core 11 shown in FIG. 1, the replica master 23 is removed from the electroformed layer 24, and the inner core 11 shown in FIG. A mold 26 as shown in FIG.

The dimensional error of the molding cavity 27 of the mold 26 according to the present embodiment manufactured according to the above-described procedure is 3 with respect to the cavity 12 of the inner core 11 serving as the mother die.
It was within μm, and it was confirmed that transfer was performed with extremely high precision.

[0025]

According to the method for manufacturing a mold of the present invention, the reactive curable resin is filled into the cavity so as to rise from the upper end of the cavity of the mother die and cured, and the upper end surface of the cured reactive curable resin is machined smoothly. By processing, the release plate is joined integrally with the adhesive, and the release plate is separated from the mother die, so that the reactive cured resin is removed from the cavity as a replica master, so molding of complex shapes It is possible to easily manufacture a mold having high precision dimensions and shapes having a cavity and a thin portion in mm units. Further, a large number of highly accurate and inexpensive replica masters and dies can be manufactured from one master without damaging the cavity of the master.

When the cavity is filled with the reactive curable resin, the reactive curable resin is filled and cured so that the reactive curable resin does not overflow from the cavity. When the cured resin is filled so as to rise from the upper end of the cavity of the matrix, it is possible to confirm the state of close contact of the reactive cured resin with the cavity.

When deaeration is performed on the reactive cured resin filled in the cavity before the reactive cured resin is cured, particularly when the reaction is performed in a vacuum atmosphere, the reactive cured resin is reliably applied to the cavity. The replica master having good transferability can be manufactured.

When the molded resin is subjected to electroforming and the electroformed mold material is machined as a mold to remove the reactive cured resin, a molding cavity having a complicated shape, It is possible to easily manufacture a highly accurate mold having a thin portion in a unit of mm.

When the reactive curable resin is removed from the cavity by releasing the reactive curable resin from the cavity by pressing the knock pin against the release plate, the reactive curable resin can be reliably released from the cavity.

[Brief description of the drawings]

FIG. 1 is a sectional view of an inner core in an embodiment of a mold manufacturing method according to the present invention.

FIG. 2 is a sectional view of a matrix unit incorporating the inner core shown in FIG.

FIG. 3 is a cross-sectional view illustrating a procedure of manufacturing a mold using the matrix unit illustrated in FIG. 2 together with FIGS. 4 to 9, and illustrates a state in which a cavity is filled with a reactive curable resin.

FIG. 4 is a cross-sectional view showing a manufacturing procedure of the mold using the matrix unit shown in FIG. 2 together with FIGS. 3, 5 to 9, and filled with a reactive cured resin so as to rise from the upper end of the cavity. Indicates a state.

5 is a sectional view showing a manufacturing procedure of a mold using the matrix unit shown in FIG. 2 together with FIG. 3, FIG. 4, and FIG. 6 to FIG. Indicates the processed state.

FIG. 6 is a cross-sectional view showing a manufacturing procedure of a mold using the matrix unit shown in FIG. 2 together with FIGS. 3 to 5 and FIGS. 7 to 9; Represents the state of being joined.

FIG. 7 is a cross-sectional view showing a procedure for manufacturing a mold using the matrix unit shown in FIG. 2 together with FIGS. 3 to 6, 8 and 9, in a state where the reactive hardening resin is die-cut from the cavity. Represents

FIG. 8 is a cross-sectional view showing a procedure for manufacturing a mold using the matrix unit shown in FIG. 2 together with FIGS. 3 to 7 and 9, and shows a state in which a replica master has been subjected to electroforming.

FIG. 9 is a cross-sectional view illustrating a manufacturing procedure of a mold using the matrix unit illustrated in FIG. 2 together with FIGS. 3 to 8, and illustrates a finally processed mold.

[Explanation of symbols]

 REFERENCE SIGNS LIST 11 inner core 12 cavity 13 mother unit 14 outer core 15 connecting plate 16 cavity 17 knock pin through hole 18 ultraviolet curing resin 19 upper end surface 20 smooth surface 21 release plate 22 knock pin 23 replica master 24 molding surface 25 electroforming layer 26 gold Mold 27 Mold cavity

Claims (8)

[Claims] 1. A method of manufacturing a mold having a molding cavity having the same shape as the cavity of the matrix using a replica master having a shape corresponding to the cavity of the matrix, comprising: Filling the cavity so as to rise from the upper end surface of the mold; curing the reactive curable resin; machining the upper end surface of the cured reactive curable resin smoothly; Integrally bonding a release plate to the upper end surface of the reactive cured resin via an adhesive, and separating the release plate from the matrix, thereby forming the cavity with the reactive cured resin as a replica master. And a step of removing the mold from the mold. 2. The step of filling the cavity with the reactive curable resin, the step of filling the reactive curable resin so that the reactive curable resin does not overflow from the cavity; 2. The method according to claim 1, further comprising: curing the reactive curable resin; and filling the reactive curable resin further from the cured reactive curable resin so as to rise from the upper end surface of the matrix. 3. The method for manufacturing a mold according to 1. 3. The method according to claim 1, further comprising a step of defoaming the reactive curable resin filled in the cavity before the step of curing the reactive curable resin. Item 3. The mold manufacturing method according to Item 2. 4. The method according to claim 3, wherein the step of defoaming the reactive cured resin is performed in a vacuum atmosphere. 5. A step of electroforming the die-cut reactive hardening resin, a step of machining the electroformed mold material as a mold, and a step of machining the electroformed mold material from the machined mold. The method according to claim 1, further comprising a step of removing the reactive cured resin. 6. The metal according to claim 5, wherein the step of removing the reactive cured resin from the cavity includes a step of abutting a knock pin against the release plate and separating the knock pin from the matrix. Mold manufacturing method. 7. A replica master manufactured by the mold manufacturing method according to claim 1. 8. A mold manufactured by the mold manufacturing method according to claim 5.